The present invention relates to an inertia detecting transducer for use in automobiles, aircraft, cruising vessels and the like transportation equipment, cameras, video cameras and the like imaging apparatus and input devices of electronic apparatus, etc.
Application field of the inertia detecting transducer includes a video camera. According to a known configuration of such transducers, the detection element and the circuit component are housed in a case.
In the structure where a circuit component and a detection element are housed in a single case, the detection element is exposed to a risk of contamination with gas or organic substance evaporated from resin adhesive used for fixing the circuit component in the case. Solder and flux used for connecting the circuit component may also a source of the contamination. The contamination leads to deterioration of the detection element in the detection characteristics.
Recently, a both-ends-open case with a partition to provide two chambers is used; one chamber for housing a detection element while the other for housing a circuit component. Thereby, it is intended to prevent the gas or organic substance generated from resin adhesive, as well as solder and flux used for connecting circuit component, from sneaking into the chamber of detection element.
In the above two-chambered configuration, a detection element is mounted in one chamber and the detection characteristic is adjusted, and then a circuit element is mounted in the other chamber, and the characteristics are inspected after adjusting operation.
In case a circuit component is damaged inadvertently during the mounting work or in the characteristics adjustment, not only the circuit component itself but also the entire detection element and the case are destined to be a waste. This is a substantial disadvantage in cost.
Even if sequence of the assembly operation is reversed, namely first mounting a circuit component and then a detection element, similar disadvantage is unavoidable.
It may be possible to replace a damaged circuit component by removing the damaged one from the other chamber of the case. However, removing a circuit component, which is fixed to case with resin adhesive and solder, is not an easy job. Even if a circuit component is successfully removed, the case might get a mechanical deformation.
The present invention aims to offer an inertia detecting transducer that features a high reliability at the detection element. If a part of the inertia detecting transducer is damaged, either one of the detection element and the circuit component remaining undamaged can be saved for re-utilization.
An inertia detecting transducer of the present invention comprises a first case, which has an opening and contains a circuit component. The first case is further provided with an external electrode and a first connection electrode. A second case of the inertia detecting transducer contains a detection element, and an opening of which case is sealed with a sealing plate. The second case is further provided with a second connection electrode. The second case is attached to the first case so that the former covers opening of the latter. And the second connection electrode and the first connection electrode are electrically coupled.
In the above-described configuration, the detection element, which is the key sensing component, is kept free from depositing of gas and organic substance generated from resin adhesive used for fixing a circuit component, and sticking of solder and flux as well. Therefore, the detection element of inertia detecting transducers in the present invention maintains a high reliability. Furthermore, even if the inertia detecting transducer is partly damaged, either one of the detection element and the circuit component left intact can be re-used.